It is used to get a close-up view of an animal or bird. I've used something like this in a state park or nature reserve, to get a good view of an eagle in flight. It wasn't free, though, I needed a supply of quarters to use it.
...Is it the front of one of those 25-cents-a-pop stereo telescopes, like the kinds on Coney Island-style piers and on the observation deck of the Empire State Building where you deposit yer quarter and get to spy on far-away things for 30 seconds or whatever?
I don't partake.....much to the amazement of many I'm sure.....I am quite the little angel..Now..If I believed in angels that might mean something...:)